Minimum amount of Taper

# What is minimum of amount of taper that should be maintained for an ideal tooth preparation?
a) 4 Degree
b) 5 Degree
c) 6 Degree
d) 12 Degree

The correct answer is D. 12 degrees.

Some important points on tapers:
• The relationship of one wall of preparation to the long axis of that preparation is the inclination of that wall. • Sum of the inclination of two opposing walls gives the taper of the preparation.
• Recommended taper is 3-12 degree. According to Schillinberg 6 degree is recommended.
• Minimum taper that is necessary to insure the absence of undercuts -12 degree.
• A taper or total convergence of 16 degrees has been proposed as being achievable clinically while still affording adequate retention. This probably an acceptable overall target. It can be as low as 10 degree on preparations of anterior teeth and as high as 22 degrees on molars.

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CPC Line

# Transverse line extending from or between the middle of upper canine and incisive fossa is called:
a) Horizontal line
b) Orientation line
c) Transverse line
d) CPC line

The correct answer is D. CPC line.

Canine-papillary-canine line (CPC line) is used as a guide to orient the upper canine teeth in complete dentures. The incisive papilla is a stable landmark for arranging labial surfaces of central incisors 10mm anterior to the incisive papilla. The tips of canines should be set on a horizontal line which pass through the posterior border of incisive papilla.

Palatopharyngeal Incompetence

# Palatopharyngeal incompetence is treated by?
a) Palatal lift prosthesis
b) Obturator prosthesis
c) Pharyngeal speech prosthesis
d) Pharyngeal bulb prosthesis

The correct answer is A. Palatal lift prosthesis.

Palatal lift prosthesis is useful for patients with velopharyngeal incompetence who exhibit compromised motor control of the soft palate & related musculature. The objective of palatal lift prosthesis is to displace the soft palate to the level of normal palatal elevation, enabling closure by pharyngeal action.

Over Dentures in Prosthodontics

# The use of selected initial roots in over denture therapy is called :
a) Overlaying denture therapy
b) Biologic denture therapy
c) Submucosal vital root retention
d) Submerged denture therapy

The correct answer is C. Submucosal vital root retention.

In over dentures, anterior abutments are preferred over posterior abutments since the anterior ridge is more vulnerable to resorption than the posterior ridge.

Serum alkaline phosphate

# Serum alkaline phosphate is increased in all EXCEPT:
A. Paget's disease
B. Fibrous dysplasia
C. Osteomyelitis
D. Hyperparathyroidism

- In Paget's disease and hyperparathyroidism the level of Serum alkaline phosphate is elevated.

- In fibrous dysplasia, the levels are elevated initially.

- In Osteomyelitis, the level stays normal, so is the answer.

Oral manifestations of osteogenesis imperfecta

- large head size

- frontal bossing

- maxillary hypoplasia

- bulbous crowns of teeth with Dentinogenesis imperfecta and blue or brown translucence (opalescent teeth)

- Class III mal occlusion with anterior and posterior cross bite.

- Severe attrition of deciduous teeth

- Multiple impacted permanent teeth

- Excessive bruising tendency

- increased incidences of development of osteitis and osteomyelitis following extraction of teeth. 

Periapical granuloma vs Periapical cemental Dysplasia

# Difference between periapical granuloma and periapical cemental dysplasia:
A. Vitality
B. Histologically
C. Radio graphically
D. Culture media

The correct answer is A. Vitality

Periapical granuloma

The tooth in Periapical granuloma is non vital and may be slightly tender to percussion but otherwise symptoms may be minimal.

- Periapical cemento-osseous dysplasia (osseous dysplasia; cemental dysplasia; cementomas).

→ Periapical cemento-osseous dysplasia predominantly involves the periapical region of the anterior mandible.

→ Solitary lesions may occur but multiple foci are present more frequently.

There is a marked predilection for female patients (ranging from 10: 1 to 14: 1) and approximately 70 % of cases affect blacks.

→ Most patients are diagnosed initially between the ages of 30 and 50, with the diagnosis almost never made in individuals under the age of 20 years. 

Teeth associated with the lesions are almost invariably vital and seldom have restorations.

→ Periapical cemento-osseous dysplasia is an asymptomatic condition that is discovered when radiographs are taken for other purposes.

→ Early lesions appear as circumscribed areas of radiolucency involving the apical area of a tooth. At this stage, the lesion cannot be differentiated radiographically from a periapical granuloma or periapical cyst.

With time adjacent lesions often fuse to form a linear pattern of radiolucency that envelopes the apices of several teeth.

Diabetes mellitus symptoms

# History of excessive thirst, hunger, micturition during nights and recent loosening of teeth usually indicate that the patient is suffering from:
A Hypertension
B Hyperthyroidism
C Diabetes mellitus
D Glomerulonephritis

The correct answer is C. Diabetes Mellitus.